Multicast traceroute over MPLS/BGP IP multicast VPN

• US 8,339,973 B1
• Filed: 09/07/2010
• Issued: 12/25/2012
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Aggarwal, Rahul, Pichumani, Swaminathan
• Primary Examiner(s): LY, ANH VU H
• Application Number:
  US12/876,871
• Time in Patent Office: 840 Days
• Field of Search: None
• US Class Current: 370/248
• CPC Class Codes: H04L 12/1863 comprising mechanisms for improved reliability, e.g. status reports arrangements for detecting or preventing errors by carrying supervisory signal the return channel H04L1/16
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route

Abstract

The subject matter of this specification can be implemented in, among other things, a method that includes receiving, at a first network device that is associated with an MVPN, an mtrace message that identifies a source device that is associated with the MVPN and that is separated from the first network device by an MPLS network. The method further includes determining an LSP from the first network device to a second network device that is associated with the MVPN and that is separated from the first network device by the MPLS network. The method further includes adding an IP header to the mtrace message, the IP header including a destination address set to a localhost loopback IP address. The method further includes encapsulating the mtrace message with an MPLS label stack that causes the encapsulated mtrace message to reach an instance of the MVPN on the second network device.

Claims

1. A method comprising:

receiving, at a first network device that is associated with a multicast virtual private network (MVPN), a multicast traceroute message that identifies a source device that is associated with the MVPN and that is separated from the first network device by a multi-protocol label switching (MPLS) network;

determining a label switched path (LSP) from the first network device to a second network device that is associated with the MVPN and that is separated from the first network device by the MPLS network;

adding an Internet Protocol (IP) header to the multicast traceroute message, the IP header comprising a destination address set to a localhost loopback IP address that causes the multicast traceroute message to be processed in a control plane of the second network device;

encapsulating the multicast traceroute message with an MPLS label stack comprising an inner MPLS label and an outer MPLS label, the MPLS label stack causing the encapsulated multicast traceroute message to reach an instance of the MVPN on the second network device; and

transmitting the encapsulated multicast traceroute message from the first network device to the second network device via the LSP.

2. The method of claim 1, wherein the MVPN comprises a border gateway protocol (BGP) MPLS IP MVPN.

3. The method of claim 1, wherein the outer label is based on the determined LSP, and wherein the inner label is based on the instance of the MVPN on the second network device.

4. The method of claim 3, wherein the inner label comprises information that is used to identify a virtual routing and forwarding (VRF) table that corresponds to the instance of the MVPN on the second network device.

5. The method of claim 1, wherein determining the LSP comprises performing a unicast route lookup towards the source device.

6. The method of claim 1, wherein the localhost loopback IP address is 127.0.0.1 in IP version 4 (IPv4).

7. The method of claim 1, wherein the localhost loopback IP address is :

;

1 in IP version 6 (IPv6).

8. The method of claim 1, wherein the first and second network devices are provider edge routing devices.

9. A non-transitory computer readable storage medium including instructions that, when executed, cause a programmable processor to:

receive, at a first network device that is associated with a multicast virtual private network (MVPN), a multicast traceroute message that identifies a source device that is associated with the MVPN and that is separated from the first network device by a multi-protocol label switching (MPLS) network;

determine a label switched path (LSP) from the first network device to a second network device that is associated with the MVPN and that is separated from the first network device by the MPLS network;

add an Internet Protocol (IP) header to the multicast traceroute message, the IP header comprising a destination address set to a localhost loopback IP address that causes the multicast traceroute message to be processed in a control plane of the second network device;

encapsulate the multicast traceroute message with an MPLS label stack comprising an inner MPLS label and an outer MPLS label, the MPLS label stack causing the encapsulated multicast traceroute message to reach an instance of the MVPN on the second network device; and

transmit the encapsulated multicast traceroute message from the first network device to the second network device via the LSP.

10. The computer readable storage medium of claim 9, wherein the MVPN comprises a border gateway protocol (BGP) MPLS IP MVPN.

11. The computer readable storage medium of claim 9, wherein the outer label is based on the determined LSP, and wherein the inner label is based on the instance of the MVPN on the second network device.

12. The computer readable storage medium of claim 11, wherein the inner label comprises information that is used to identify a virtual routing and forwarding (VRF) table that corresponds to the instance of the MVPN on the second network device.

13. The computer readable storage medium of claim 9, wherein determining the LSP comprises performing a unicast route lookup towards the source device.

14. The computer readable storage medium of claim 9, wherein the localhost loopback IP address is 127.0.0.1 in IP version 4 (IPv4).

15. The computer readable storage medium of claim 9, wherein the localhost loopback IP address is :

;

1 in IP version 6 (IPv6).

16. The computer readable storage medium of claim 9, wherein the first and second network devices are provider edge routing devices.

17. A routing device comprising:

a first interface configured to receive a multicast traceroute message that identifies a source device that is associated with a multicast virtual private network (MVPN) with which the routing device is associated, the source device being separated from the routing device by a multi-protocol label switching (MPLS) network;

a routing engine configured to determine a label switched path (LSP) to a network device that is associated with the MVPN and that is separated from the routing device by the MPLS network, and to encapsulate the multicast traceroute message with an MPLS label stack comprising an inner MPLS label and an outer MPLS label, the MPLS label stack causing the encapsulated multicast traceroute message to reach an instance of the MVPN on the network device;

an mtrace support module executed by hardware of the routing device configured to add an Internet Protocol (IP) header to the multicast traceroute message, the IP header comprising a destination address set to a localhost loopback IP address that causes the multicast traceroute message to be processed in a control plane of the network device; and

a second interface configured to transmit the multicast traceroute message to the network device via the LSP.

18. A system comprising:

a first network device that is associated with a multicast virtual private network (MVPN); and

a second network device that is associated with the MVPN and that is separated from the first network device by a multi-protocol label switching (MPLS) network;

wherein the first network device receives a multicast traceroute message that identifies a source device that is associated with the MVPN and that is separated from the first network device by the MPLS network, determines a label switched path (LSP) from the first network device to the second network device, adds an Internet Protocol (IP) header to the multicast traceroute message, the IP header comprising a destination address set to a localhost loopback IP address that causes the multicast traceroute message to be processed in a control plane of the second network device, encapsulates the multicast traceroute message with an MPLS label stack comprising an inner MPLS label and an outer MPLS label, the MPLS label stack causing the encapsulated multicast traceroute message to reach an instance of the MVPN on the second network device, and transmits the encapsulated multicast traceroute message from the first network device to the second network device via the LSP; and

wherein the second network device receives the encapsulated multicast traceroute message transmitted from the first network device, determines that the encapsulated multicast traceroute message is destined for the instance of the MVPN on the second network device based on the MPLS label stack of the MPLS encapsulated multicast traceroute message, and transmits the multicast traceroute message to the control plane of the second network device based on the IP header of the multicast traceroute message.

19. A method comprising:

receiving, at a second network device that is associated with a multicast virtual private network (MVPN), a multi-protocol label switching (MPLS) encapsulated multicast traceroute message sent from a first network device that is associated with the MVPN, the multicast traceroute message identifying a source device that is associated with the MVPN and that is separated from the first network device by an MPLS network;

determining that the MPLS encapsulated multicast traceroute message is destined for an instance of the MVPN on the second network device based on an MPLS label stack of the MPLS encapsulated multicast traceroute message; and

transmitting the multicast traceroute message to a control plane of the second network device based on an Internet Protocol (IP) header of the multicast traceroute message, the IP header comprising a destination address set to a localhost loopback IP address.

20. The method of claim 19, wherein the MVPN comprises a border gateway protocol (BGP) MPLS IP MVPN.

21. The method of claim 19, wherein an outer label of the MPLS label stack is based on a label switched path (LSP) from the first network device to the second network device, and wherein the inner label is based on the instance of the MVPN on the second network device.

22. The method of claim 21, wherein the inner label comprises information that is used to identify a virtual routing and forwarding (VRF) table that corresponds to the instance of the MVPN on the second network device.

23. The method of claim 21, wherein the LSP is determined by the first network device performing a unicast route lookup towards the source device.

24. The method of claim 19, wherein the localhost loopback IP address is 127.0.0.1 in IP version 4 (IPv4).

25. The method of claim 19, wherein the localhost loopback IP address is :

;

1 in IP version 6 (IPv6).

26. The method of claim 19, wherein the first and second network devices are provider edge routing devices.